Evidence for a role for the group I metabotropic glutamate receptor in the inhibitory effect of tumor necrosis factor-α on long-term potentiation

Pro-inflammatory cytokines are known to be elevated in several neuropathological states that are associated with learning and memory. We have previously demonstrated in our laboratory that the inhibition of long-term potentiation (LTP) in the dentate gyrus region of the rat hippocampus, by tumor necrosis factor (TNF)-α, represents a biphasic response, an early phase dependent on p38 mitogen activated protein kinase (MAPK) activation and a later phase, possible dependent on protein synthesis. Many of the factors involved in the early modulation of LTP by TNF-α have yet to be elucidated. This study investigated if metabotropic glutamate receptors (mGluRs) are functionally linked to the inhibitory effect of TNF-α on LTP in the rat dentate gyrus in vitro. We report that the impairment of early-LTP by TNF-α is significantly attenuated by prior application of the group I/II mGluR antagonist MCPG and more specifically the mGluR5 antagonist MPEP. Since TNF-α is now known to cause transient increases in intracellular Ca2+ levels from ryanodine-sensitive stores, we explored the possibility that disruption of intracellular Ca2+ homeostasis could be involved. Ryanodine was found to significantly reverse the inhibition of LTP by TNF-α. From these studies we propose that the TNF-α inhibition of LTP is dependent upon the activation of TNFR1 and mGlu5-receptors. Importantly this study provides the first proof of the involvement of ryanodine-sensitive intracellular Ca2+ stores in TNF-α mediated inhibition of LTP

Citizen or consumer? Reconsidering energy citizenship

The transition to more sustainable energy systems has set about redefining the social roles and responsibilities of citizens. Implicit in this are expectations around participation, though the precise contours of what this might mean remain open. Debates around the energy transition have been skewed towards a normative construct of what it means to be a ‘good citizen’, the parameters for which are shaped by predetermined visions of statist and/or market-driven determinations of the energy systems of the future. This article argues that concepts such as ‘energy citizen’ are co-opted to reflect popular neoliberal discourses, and ignore crucial questions of unequal agency and access to resources. Paradoxically, official discourses that push responsibility for the energy transition onto the ‘citizen-as-consumer’ effectively remove agency from citizens, leaving them largely disconnected and disempowered. Consequently, energy citizenship needs to be reconceptualised to incorporate more collective and inclusive contexts for action. Considering how much energy consumption occurs in (traditionally female) domestic spheres, do conventional notions of citizenship (especially with regards to its associated rights and duties) need to be recalibrated in order for the concept to be usefully applied to the energy transition

Self-Diffusion of a Polymer Chain in a Melt

Self-diffusion of a polymer chain in a melt is studied by Monte Carlo simulations of the bond fluctuation model, where only the excluded volume interaction is taken into account. Polymer chains, each of which consists of $N$ segments, are located on an $L \times L \times L$ simple cubic lattice under periodic boundary conditions, where each segment occupies $2 \times 2 \times 2$ unit cells. The results for $N=32, 48, 64, 96, 128, 192, 256, 384$ and 512 at the volume fraction $\phi \simeq 0.5$ are reported, where $L = 128$ for $N \leq 256$ and L=192 for $N \geq 384$. The $N$-dependence of the self-diffusion constant $D$ is examined. Here, $D$ is estimated from the mean square displacements of the center of mass of a single polymer chain at the times larger than the longest relaxation time. From the data for $N = 256$, 384 and 512, the apparent exponent $x_{\rm d}$, which describes the apparent power law dependence of $D$ on $N$ as $D \propto N^{- x_{\rm d}}$, is estimated as $x_{\rm d} \simeq 2.4$. The ratio $D \tau /$ seems to be a constant for $N = 192, 256, 384$ and 512, where $\tau$ and $$ denote the longest relaxation time and the mean square end-to-end distance, respectively.Comment: 4 pages, 3 figures, submitted to J. Phys. Soc. Jp

A multi-bacteriocin cheese starter system comprising nisin and lacticin 3147 in Lactococcus lactis, in combination with plantaricin from Lactobacillus plantarum

Functional starter cultures demonstrating superior technological and food safety properties are advantageous to the food fermentation industry. We evaluated the efficacy of single and double bacteriocin-producing starters of Lactococcus lactis capable of producing the Class I bacteriocins, nisin A and/or lacticin 3147 in terms of starter performance. Single producers were generated by mobilising the conjugative, bacteriophage resistance plasmid pMRC01, encoding lacticin genetic determinants, or the conjugative transposon Tn5276, encoding nisin genetic determinants, to the commercial starter L. lactis CSK2775. The effect of bacteriocin co-production was examined by superimposing pMRC01 into the newly constructed nisin transconjugant. Transconjugants were improved with regard to antimicrobial activity and bacteriophage insensitivity when compared to the recipient strain and the double producer was immune to both bacteriocins. Bacteriocin production in the starter was stable, although the recipient strain proved to be a more efficient acidifier than transconjugant derivatives. Overall, combining Class I bacteriocins (the double-producer or a combination of single producers) proved as effective as individual bacteriocins for controlling Listeria innocua growth in laboratory-scale cheeses. However, using the double producer in combination with the Class II bacteriocin producer Lactobacillus plantarum, or the lacticin producer with the Class II producer, proved most effective for reducing bacterial load. As emergence of bacteriocin tolerance was reduced 10-fold in the presence of nisin and lacticin, we suggest that the double producer in conjunction with the Class II producer could serve as a protective culture providing a food-grade, multi-hurdle approach to control pathogenic growth in a variety of industrial applications. IMPORTANCE: We generated a suite of single and double-bacteriocin producing starter cultures capable of generating the Class I bacteriocins lacticin 3147 or nisin or both bacteriocins simultaneously via conjugation. The transconjugants exhibited improved bacteriophage resistance and antimicrobial activity. The single producers proved as effective as the double-bacteriocin producer at reducing Listeria numbers in laboratory-scale cheese. However, combining the double producer or the lacticin producing starter with a Class II bacteriocin producer, Lactobacillus plantarum LMG P-26358, proved most effective at reducing Listeria numbers, and was significantly better than a combination of the three bacteriocin producing strains, as the double producer is not inhibited by either of the Class I bacteriocins. Since the simultaneous use of lacticin and nisin should reduce the emergence of bacteriocin tolerant derivatives this study suggests that a protective starter system produced by bacteriocin stacking is a worthwhile multi-hurdle approach for food safety applications

Pleasure and pedagogy: the consumption of DVD add-ons among Irish teenagers

This article addresses the issue of young people and media use in the digital age, more specifically the interconnection between new media pleasures and pedagogy as they relate to the consumption of DVD add-ons. Arguing against the view of new media as having predominantly detrimental effects on young people, the authors claim that new media can enable young people to develop media literacy skills and are of the view that media literacy strategies must be based on an understanding and legitimating of young people's use patterns and pleasures. The discussion is based on a pilot research project on the use patterns and pleasures of use with a sample of Irish teenagers. They found that DVDs were used predominantly in the home context, and that, while there was variability in use between the groups, overall they developed critical literacy skills and competences which were interwoven into their social life and projects of identity construction. The authors suggest that these findings could be used to develop DVDs and their add-on features as a learning resource in the more formal educational setting and they go on to outline the potential teaching benefits of their use across a range of pedagogical areas

Psychological talent predictors in youth soccer: A systematic review of the prognostic relevance of psychomotor, perceptual-cognitive and personality-related factors

Within the multidimensional nature of soccer talent, recently there has been an increasing interest in psychological characteristics. The aim of this present research was to systematically review the predictive value of psychological talent predictors and provide better comprehension of the researchers’ methodological approaches and the empirical evidence for individual factors (i.e., psychomotor, perceptual-cognitive and personality-related). Results highlighted heterogeneous study designs (e.g., participants, measurement methods, statistical analyses) which may limit the comparability of studies’ findings. Analyzing the number of included studies, psychomotor (n = 10) and personality-related factors (n = 8) received more consideration within the literature than perceptual-cognitive factors (n = 4). In regard to empirical evidence, dribbling (0.47 ≤ d ≤ 1.24), ball control (0.57 ≤ d ≤ 1.28) and decision-making (d = 0.81) demonstrated good predictive values as well as the achievement motives hope for success (0.27 ≤ d ≤ 0.74) and fear of failure (0.21 ≤ d ≤ 0.30). In conclusion, there is growing acceptance of the need for more complex statistical analyses to predict future superior performance based on measures of current talent. New research addresses the necessity for large-scale studies that employ multidisciplinary test batteries to assess youth athletes at different age groups prospectively.</div

Atmospheric composition and climate impacts of a future hydrogen economy

Hydrogen is expected to play a key role in the global energy transition to net zero emissions in many scenarios. However, fugitive emissions of hydrogen into the atmosphere during its production, storage, distribution and use could reduce the climate benefit and also have implications for air quality. Here we explore the atmospheric composition and climate impacts of increases in atmospheric hydrogen abundance using the UKESM1 chemistry-climate model. We find that increases in hydrogen result in increases in methane, tropospheric ozone and stratospheric water vapour, resulting in a positive radiative forcing. However, some of the impacts of hydrogen leakage are partially offset by potential reductions in emissions of methane, carbon monoxide, nitrogen oxides and volatile organic compounds from the consumption of fossil fuels. We derive a new methodology for determining indirect Global Warming Potentials from steady-state simulations which is applicable to both shorter-lived species and those with intermediate and longer lifetimes, such as hydrogen. Using this methodology, we determine a 100-year Global Warming Potential for hydrogen of 12 &plusmn; 6. To maximise the benefit of hydrogen as an energy source, emissions associated with hydrogen leakage and emissions of the ozone precursor gases need to be minimised.</p

Stimulating Neoblast-Like Cell Proliferation in Juvenile Fasciola hepatica Supports Growth and Progression towards the Adult Phenotype In Vitro

Fascioliasis (or fasciolosis) is a socioeconomically important parasitic disease caused by liver flukes of the genus Fasciola. Flukicide resistance has exposed the need for new drugs and/or a vaccine for liver fluke control. A rapidly improving 'molecular toolbox' for liver fluke encompasses quality genomic/transcriptomic datasets and an RNA interference platform that facilitates functional genomics approaches to drug/vaccine target validation. The exploitation of these resources is undermined by the absence of effective culture/maintenance systems that would support in vitro studies on juvenile fluke development/biology. Here we report markedly improved in vitro maintenance methods for Fasciola hepatica that achieved 65% survival of juvenile fluke after 6 months in standard cell culture medium supplemented with 50% chicken serum. We discovered that this long-term maintenance was dependent upon fluke growth, which was supported by increased proliferation of cells resembling the "neoblast" stem cells described in other flatworms. Growth led to dramatic morphological changes in juveniles, including the development of the digestive tract, reproductive organs and the tegument, towards more adult-like forms. The inhibition of DNA synthesis prevented neoblast-like cell proliferation and inhibited growth/development. Supporting our assertion that we have triggered the development of juveniles towards adult-like fluke, mass spectrometric analyses showed that growing fluke have an excretory/secretory protein profile that is distinct from that of newly-excysted juveniles and more closely resembles that of ex vivo immature and adult fluke. Further, in vitro maintained fluke displayed a transition in their movement from the probing behaviour associated with migrating stage worms to a slower wave-like motility seen in adults. Our ability to stimulate neoblast-like cell proliferation and growth in F. hepatica underpins the first simple platform for their long-term in vitro study, complementing the recent expansion in liver fluke resources and facilitating in vitro target validation studies of the developmental biology of liver fluke

Interface barriers at the interfaces of polar GaAs(111) faces with Al2O3

Internal photoemission measurements of barriers for electrons at interfaces between GaAs(111) and atomic-layer deposited Al2O3 indicate that changing the GaAs polar crystal face orientation from the Ga-terminated (111)A to the As-terminated (111)B has no effect on the barrier height and remains the same as at the non-polar GaAs(100)/Al2O3 interface. Moreover, the presence of native oxide on GaAs(111) or passivation of this surface with sulphur also have no measurable influence on the GaAs(111)/Al2O3 barrier. These results suggest that the orientation and composition-sensitive surface dipoles conventionally observed at GaAs surfaces are effectively compensated at GaAs/oxide interfaces. (C) 2012 American Institute of Physics. (http://dx.doi.org/10.1063/1.3698461